Quantitative structure-activity studies of octopaminergic 2-(arylimino)thiazolidines and oxazolidines against the nervous system of Periplaneta americana L.
The quantitative structure-activity relationship (QSAR) of octopaminergic 2-(arylimino)thiazolidines (AITs) and 2-(arylimino)oxazolidines (AIOs) against the thoracic nerve cord of the American cockroach, Periplaneta americana L., was analysed using reported physicochemical parameters and regression analysis. The more electron-donating, the less bulky at m-position, and the more hydrophobic the substituent, the greater the activity. The plots of observed log Vmax values against calculated log Vmax values having substituents on the m-position deviated downwards from those of compounds having substituents at the 0- and/or p-positions. The more hydrophobic and the more electron-withdrawing the substituent, the greater the activity. AIO with a 2, 3, 4-trichlorophenyl group (58) was more active than its thiazolidine derivative, 2-(2,3,4-trichlorophenylimino)thiazolidine (38) in terms of Vmax:Vmax of 58 was 30% relative to octopamine (OA), whereas that of 38 has been 9% relative to OA, respectively. Superimposition of energy-minimized OA and 58 revealed structural and conformational similarities that might account for the high activity of 58.
Hirashima
A
A
Department of Agricultural Chemistry, Kyushu University, Fukuoka, Japan.
Tomita
J
J
Pan
C
C
Taniguchi
E
E
Eto
M
M
D000818:Animals; D003198:Computer Simulation; D004789:Enzyme Activation; D007097:Imines / Q000737:chemistry / Q000494:pharmacology*; D007700:Kinetics; D008958:Models, Molecular; D009420:Nervous System / Q000187:drug effects*; D009655:Octopamine / Q000819:agonists*; D010080:Oxazoles / Q000737:chemistry / Q000494:pharmacology*; D010526:Periplaneta / Q000187:drug effects*; D013329:Structure-Activity Relationship; D013844:Thiazoles / Q000737:chemistry / Q000494:pharmacology*
D007097:Imines; D010080:Oxazoles; D013844:Thiazoles; D009655:Octopamine